Corrosion inhibition effect of the synthetized 2-butyl-3-({4-[2-(2H-1,2,3,4tetrazol-5-yl)phenyl]phenyl}methyl)-1,3-diazaspiro[4.4]non-1-en-4-one drug on CS in 1.0 M HCl electrolyte: electrochemical, spectroscopic and theoretical investigations

The synthesized IRBESARTAN drug, namely, 2-butyl-3-({4-[2-(2H1,2,3,4-tetrazol-5-yl)phenyl]phenyl}methyl)-1,3-diazaspiro[4.4]non-1-en-4-one (IRBESARTAN) was prepared and characterized using NMR spectroscopy. The obtained product was evaluated by electrochemical and spectroscopic measurements as an anticorrosion for carbon steel (CS) in 1.0 M HCl electrolyte. It is obtained that the IRBESARTAN reacts as a good and mixed -type inhibitor, where its performance rises with its concentration and immersion time, which offered inhibition efficiency up to 94 % according to EIS measurements. In addition, the temperature influence on the CS dissolution rate was considered without and with IRBESARTAN at the optimum concentration. It is indicated that it is performant at high temperature. Additionally, the thermodynamic and activation data discovered that the IRBESARTAN particles adsorption on the CS area is an endothermic procedure. Indeed, its action obeys to the Langmuir model, relating both physical and chemical actions. The scanning electron microscopy (SEM) analysis demonstrated the construction of a defensive deposit, confirming the electrochemical findings. Finally, the DFT calculations and MD simulation explain the mode of the IRBESARTAN adsorption, and confirm the obtained experimental results.